/Engine/Source/Editor/UnrealEd/Public/FbxImporter.h
Detect if the FBX file has skeletal mesh model. If there is deformer definition, then there is skeletal mesh. In this function, we don't need to import the scene. But the open process is time-consume if the file is large.
int32 -1 if parse failed; 0 if geometry ; 1 if there are deformers; 2 otherwise
int32 GetImportType ( const [FString](API\Runtime\Core\Containers\FString) & InFilename )